Re: UFS storage support for Tensor/GS101?

[William McVicker <willmcvicker@google.com>]

On 02/06/2024, Eric Biggers wrote:
> Hi Peter,
> 
> On Tue, Feb 06, 2024 at 05:09:13PM +0000, Peter Griffin wrote:
> > Hi Eric,
> > 
> > + Will
> > 
> > On Tue, 6 Feb 2024 at 03:45, Eric Biggers <ebiggers@kernel.org> wrote:
> > >
> > > Hi Peter!  Thanks for all the hard work you've been doing on upstreaming support
> > > for Tensor/GS101.  I've tested that the latest upstream kernel is now able to
> > > boot to a serial console on Pixel 6.
> > 
> > Thanks for testing :)
> > >
> > > I'm wondering if you have any plans to upstream support for the UFS storage on
> > > that platform?  It should be able to use the already-upstream
> > > drivers/ufs/host/ufs-exynos.c driver, but changes may be required; I'm not sure
> > > how many.  I'm interested in this mainly because I'd like to upstream some
> > > patches related to inline encryption, and that depends on UFS storage working.
> > >
> > > I'm interested in helping with this, but I wanted to check to see if you know
> > > about any existing plans first.
> > 
> > We certainly want to add support for UFS upstream, and if you can help
> > out with enabling it that would be great! It would free us up to work
> > on enabling something else in parallel. From a first pass analysis of
> > the downstream UFS code it looks like ufs phy driver likely needs the
> > most attention.
> > 
> > The last UFS dependency (that I'm aware of) that is missing currently
> > is clock support for cmu_hsi2 (which I was planning on working on as
> > my next task). Also the UFS phy accesses PMU registers so that will
> > require my exynos-pmu [1] series but that is hopefully close to being
> > merged.
> > 
> > So I think we are quite close to having all the UFS dependencies in
> > place. Shall I ping you once I have some code for cmu_hsi2, and
> > hopefully that should be enough for you to start working on the UFS
> > driver and phy?
> > 
> > Thanks,
> > 
> > Peter
> 
> Yes, let me know as soon as you have some code for cmu_hsi2, and I'll try to get
> UFS working.  I don't know how hard it will be, though, so it's possible I'll
> need help from others.
> 
> Thanks,
> 
> - Eric

+Bart

Hi Eric,

Thanks for reaching out! I was planning on sending a message to you and Bart
once the UFS dependencies that Peter mentioned were close to landing. We would
love to have your help!

Bart,
I know you mentiond in the past that you looked into upstreaming the Pixel UFS
driver but were blocked on it's dependencies. Have you had a chance to see what
has landed for gs101 upstream thus far? It would be great if you could provide
feedback on your findings! And please let us know if you're interested in
collaborating with us on upstreaming the gs101 UFS bits.

Thanks,
Will